The testing on a full-scale powerplant for the Lockheed Martin F-35 wraps up P&W’s role under a four-year adaptive engine technology development (AETD) programme sponsored by the Air Force Research Laboratory (AFRL).

The testing was intended to understand the maturity of so-called “three-stream” adaptive turbofan technology as AFRL launches a $1 billion programme to develop a full-scale, 45,000lb-thrust-class prototype engine under the Adaptive Engine Transition Programme (AETP) that could be used to re-engine the F-35 and power a future combat aircraft.

“This is an important milestone on the path toward the advancement and maturation of a next generation adaptive engine which will enable the warfighter to stay well ahead of future and emerging threats,” says Matthew Bromberg, president of P&W Military Engines, in a news release.

The AFRL is using a competitive development approach for adaptive engine technology, supporting P&W and GE Aviation through the full-scale prototype stage in AETP.

With a goal to improve specific fuel consumption by 25% compared to a 2000-baseline combat aircraft engine US Air Force and Navy have been pursuing adaptive engine technology since 2006.

The adaptive engine is designed to improve efficiency by inserting a valve in the fan module that in cruise mode opens to permit a third stream of airflow – in addition to core flow and bypass flow. The third stream increases the volume of bypass flow to make the engine more efficient in producing thrust. It also creates a new heat-sink within the engine, which allows the designers to improve fuel efficiency by increasing temperatures inside the core.